Fish tail propeller



Nov. 2, 1937. H. c. MARTIN FISH TAIL PROPELLER Filed Jan. l5, 1937 rllllll.. Iillllll H n ww um Nm Pm .EN NN Patented Nov. 2, 1937 UNITEDSTATES EATENT OFFCE 17 Claims.

My invention relates to propellers for boats and particularly to thattype used to propel and steer small boats by hand.

Primarily my invention has for its object t provide a portable handpropeller which may be folded and carried in a small space and yet onewhich is easily mounted on a boat for use. Further it is an object ofthe invention to provide a device which propels the boat and at the sametime serves as a tiller and which accomplishes both purposes with aminimum loss of effort.

Still further it is an object of the invention to provide a device withall of the above mentioned features and also with a simplified means forreversing the propeller blade when it becomes necessary to backwater.

Other objects will in part be obvious and in part generally pointed outhereinafter.

To the attainment of the aforesaid objects and ends, the invention stillfurther resides in those `iovel details of construction, combination andLrrangement of parts, all of which will be rst fully described in thefollowing detailed description, then be pointed out in the appendedclaims, references being had to the accompanying drawing, in which:

Fig. 1 is a side elevation showing the device mounted on the stern of aboat, a portion of the stern of a boat being shown in section.

Fig. 2 is a detail elevational view of the coupling plate which carriesthe eye bolts and wing nuts.

Fig. 3 is a detail elevational View of the face of the coupling platewhich is slotted.

Fig. 4 is a detail View showing some of the more important structures incross section.

Fig. 5 is a detail side elevation showing a modified form of thepropeller blade.

Fig. 6 is a top plan view of the reversing and stroke checkingmechanism.

Fig. 7 is a detail sectional View of the ,stud 33 showing thelubricating duct.

In the drawing in which like numerals of ref erence designate like partsin all of the figures, I indicates the operators handle which is Weldedto the ere part of the main beam, said beam being indicated by 2. 3designates the rear section of the main beam which has a coupling plateWelded thereto. The plate 9 has hinged eye bolts and nuts indicated by 5and dowel pins indicated by 6,

The beam 2 carries a similar coupling plate 'l which is slotted at 8 toreceive one of the bolts 5 of plate 4 and has an aperture 4I to receivethe other bolt 5, also plate 'I had indications 9 to receive the dowelpins 6, in plate 4. These coupling plates allow the device to be readilytaken apart for carrying. In practice the eye bolt 5 which passesthrough the aperture 4| is merely loosened thus allowing the two partsof the device to be hingedly folded. Mid-way of the beam 2 is located alug I0 which serves as a pivot for the beam. The lug |D operates withinthe sleeve I2 and is held in place by pin II. The sleeve I2 is pivotedat I3 on the arm I4.

I4 is a part of the bracket I5 which is secured to the boat Il', by aclamp screw I6. An arm I8 extends from the sleeve l2 and allows `for theraising or lowering of the device by means of the adjusting screw I9.The reversing mechanism is controlled from the boat by means oi a rod 29attached to a handleZI which is pivoted at 22. A spring clasp 23 isprovided to hold the handle 2| in place. The beam 3 has welded to oneend a sleeve 24 within which another sleeve 29 operates. The reversingmechanism consists of a plate having two arms, one of which extends inthe same direction as the beam and the other at right angles thereto.-The one indicated by 28 has astud 3U to which the spring 3| is attached,the other arm is indicated by 34 and has the rod 29 attached thereto.

The parts 28, 29, 30 and 34 can be made in one piece. The propellerblade 25 has a shaft 26 which is notched at 21. The bar 36 which issecured to the propeller shaft 26 by a bolt 35 serves to limit thestroke by reason of the fact that 36 can only move the distance betweenthe adjustment screws 31. The adjustment screws 3l are adjustable withinthe up-turned ends of the bracket 40.

The spring 3| is attached to the stud 39 at one end and to the link 32at the other end. The link 32 is swivelly connected to the bar 36 by thestud 33. The stud 33 is shown in detail and has a grease duct 45therein. The two grease cups are indicated by 38 and 39. A spring 43 isprovided to keep the beam in a straight line behind the boat and isattached to the beam 2 by a stud 44 and to the sleeve I2 by a stud 42.The device is operated by a person seated in the stern of the boat whograsps the handle vI and moves it back and forth. This action causes thepropeller blade to move back andforth in the water with a motion similarto that made by the tail of a swimming fish. The propeller blade isreversed by raising the reversing handle 2| up and 'out of the clasp 23past the center of the beam and then forced downwardly until the @Tm3431s all the way over to the opposite side.

'I'he handle 2| is then clamped down into the clasp 23. The spring 3|serves to keep the propeller in a straight line with the beam and thespring 43 serves to keep the beam in a straight line with the boat thusacting as a rudder when the boat is drifting with the Wind.

The spring 3| also acts to bring the propeller blade around in line withthe beam so that the return stroke begins Without loss of motion.

Since all of the working parts except the propeller blade are aboveWater, very little effort is lost. The top of the propeller blade,Working about two inches below the surface of the Water with a stroke ofabout 15 past center each Way, noiselessly propels the boat at a fairgait.

What I claim is:

1. In a fish-tail propeller, a support, means to mount said support overthe end of a boat, a beam pivotally mounted in said support cna verticalaxis, one end of said beam extending into the boat and the other endextending to the rear of the boat and carrying a vertical sleeve, apropeller blade having a shaft pivotally journalled in said sleeve, alever journalled on an axis coincident With that of said propellersshaft, resilient means connecting said lever with said propeller bladesshaft and continuously tending to maintain the propeller blade in linewith said beam.

2. In a fish-tail propeller, a support, means to mount said support overthe end of a boat, a beam pivotally mounted in said support on avertical axis, one end of said beam extending into the boat and theother end extending to the rear of the boat and carrying a verticalsleeve, a propeller blade havingla shaft pivotally journalled in saidsleeve, a bell-crank lever journalled on an axis coincident with that ofsaid propellers shaft, resilient means connecting said bell-crank leverwith said propeller blades shaft and continuously tending to maintainthe propeller blade in line with said beam;

3. In a fish-tail propeller, a support, means to mount said support overthe end of a boat, a beam pivotally mounted in said support on avertical axis,one end of said beam extending into the boat and the otherend extending to the rear of the boat and carrying a vertical sleeve, apropeller blade having a shaft pivotally journalled inc said sleeve, alever journalled on an axis coincident with that of said propellersshaft, resilient means connecting said lever with said propeller bladesshaft and continuously tending to maintain the propeller blade in lineWith said beam and means to turn said lever through an arc of 180 toreverse the position of said propeller blade.

4. In a sh-tail propeller, a support, means to mount saidsupport'overthe end of a boat, a beam pivotally mounted in said supporton a vertical axis, one end of said beam extending into the boat and theother end extending to the rear of the boat and carrying a verticalsleeve, a propeller blade having a shaft pivotally journalled in saidsleeve, a bell-crank lever journalled on an axis coincident With that ofsaid propellers shaft, resilient means connecting said bell-crank leverwith said propeller blades shaft and continuously tending to maintainthe propeller blade in line with said beamand means to turn said leverlthrough an arc of 180 to reverse the position of said propeller blade.

5. In a fish-tail propeller, a support, means to mount said' supportover the end of ka boat, a

beam pivotally mounted in said support on a vertical axis, one end ofsaid beam extending into the boat and the other end extending to therear of the boat and carrying a vertical sleeve, a propeller bladehaving a shaft pivotally journalled in said sleeve, a lever journalledon an axis coincident with that of said propellers shaft, resilientmeans connecting said lever with said propeller blades shaft andcontinuously tending to maintain the propeller blade in line with saidbeam and means to limit the movement of said propeller blade inopposition to the maintaining tendency of said resilient means.

6. In a fish-tail propeller, a support, means to mount said support overthe end of a boat, a beam pivotally mounted in said support on avertical axis, one end of said beam extending into the boat and theother end extending to the rear of the boat and carrying a Verticalsleeve, a propeller blade having a shaft pivotally journalled in saidsleeve, a bell-crank'lever journalled on an axis coincident With that ofsaid propellers shaft, resilient means connecting said bell-rank leverWith said propeller blades shaft and continuously tending to maintainthe propeller blade in line with said beam and means to limit themovement of said propeller blade in opposition to the maintainingtendency of said resilient means.

'7. In a fish-tail propeller, a support, moans to mount said supportover the end of a boat, a beam pivotally mounted in said support on avertical axis, one end of said beam extending into the boat and theother end extending to the rear of the boat and carrying a verticalsleeve, a propeller blade having a-shaft pivotally journalled in saidsleeve, a lever journalled on an axis coincident With that of saidpropellers shaft, resilient means connecting said lever with saidpropeller blades shaft and continuously tending to maintain thepropeller blade in line with said beam and means to turn said leverthrough an arc of 180 to reverse the position of said propeller bladeand means to limit the movement of said propeller blade in opposition tothe maintaining tendency of said resilient means.

8. In a fish-tail propeller, a support, means to mount said support overthe end of a boat, a beam pivotally mounted in said support on avertical axis, one end of said beam extending into the boat and theother end extending to the rear of the boat and carrying a verticalsleeve, a propeller blade having a shaft pivotally journalled in saidsleeve, a bell-crank lever journalled on an axis coincident with that ofsaid propellers shaft, resilient means connecting said bell-crank leverwith said propeller blades shaft and continuously tending to maintainthe propeller blade in line With said beam and means to turn said leverthrough an arc of 180 to reverse the position of said propeller blade,and means to limit the movement of said propeller blade in opposition tothe maintaining tendency of said resilient means.

9. In a fish-tail propeller, a support, means to mount said support overthe end of a boat, a beam pivotally mounted in said support on avertical axis, one end of said beam extending into the boat and theother end extending to the rear of the boat and carrying a verticalsleeve, a propeller blade having a shaft pivotally journalled in saidsleeve, a lever journalled on an axis coincident with that of saidpropellers shaft, an arm secured at one end to said propeller bladesshaft, a spring connecting the other end of said arm to said lever invirtue of Which said propeller blade may swing on its pivot against theaction of said spring.

10. In a sh-tail propeller, a support, means to mount said support overthe end of a boat, a beam pivotally mounted in said support on avertical axis, one end of said beam extending into the boat and theother end extending to the rear of the boat and carrying a verticalsleeve, a propeller blade having a shaft pivotally journalled in saidsleeve, a lever journalled on an axis coincident with that of saidpropellers shaft, an arm secured at one end of said propeller bladesshaft, a spring connecting the other end of said arm to said lever invirtue of which said propeller blade may swing on its pivot against theaction of said spring and adjustable means to limit the swing of saidpropeller on its pivot.

11. In a fish-tail propeller, a support, means to mount said supportover the end of a boat, a l5 beam pivotally mounted in said support on avertical axis, one end of said beam extending into the boat and theother end extending to the rear of the boat and carrying a verticalsleeve, a propeller blade having a shaft pivotally journalled in saidsleeve, a lever journalled on an axis coincident with that of saidpropellers shaft, an arm secured at one end to said propeller bladesshaft, a spring connecting the other end of said arm to said lever invirtue of which said propeller blade may swing on its pivot against theaction of said spring and means to turn said lever through an arc of 180to reverse the position of said propeller blade.

12. In a sh-tail propeller, a support, means to mount said support overthe end of a boat, a beam pivotally mounted in said support on avertical axis, one end of said beam extending into the boat and theother end extending to the rear of the boat and carrying a verticalsleeve, a propeller blade having a shaft pivotally journalled in saidsleeve, a lever journalled on an axis coincident with that of saidpropellers shaft, an arm secured at one end of said propeller bladesshaft, a spring connecting the other end of said arm to said lever invirtue of which said propeller blade may swing on its pivot against theaction of said spring and adjustable means to limit the swing of saidpropeller on its pivot and means to turn said lever through an arc of180 to reverse the position of said propeller blade.

13. In a fish-tail propeller, a support, means to mount said supportover the end of a boat, a beam pivotally mounted in said support on avertical axis, one end of said beam extending into the boat and theother end extending to the rear of the boat and carrying a verticalsleeve, a propeller blade having a shaft pivotally journalled in saidsleeve, a lever journalled on an axis coincident with that of saidpropellers shaft, an arm secured at one end to said propeller bladesshaft, a spring connecting the other end of said arm to said lever invirtue of which said propeller blade may swing on its pivot against theaction of said spring and means to turn said lever through an arc of 180to reverse the position of said propeller blade, said last named meanscomprising a rod connected to said lever and extending to the boat andmanipulatable by the user, and means to hold the rod and thereby holdthe lever in either of its two operative positions.

14. In a fish-tail propeller, a support, means to mount said supportover the end of a boat, a beam pivotally mounted in said support on avertical axis, one end of said beam extending into the boat and theother end extending to the rear of the boat and carrying a verticalsleeve, a propeller blade having a shaft pivotally journalled in saidsleeve, a lever journalled on an axis coincident with that of saidpropellers shaft, an arm secured at one end of said propeller bladesshaft, a spring connecting the other end of said arm to said lever invirtue of which said propeller blade may swing on its pivot against theaction of said spring and adjustable means to limit the swing of saidpropeller on its pivot and means to turn said lever through an arc of tore- Verse the position of said propeller blade, said last named meanscomprising a rod connected to said lever and extending to the boat andmanipulatable by the user, and means to hold the rod and thereby holdthe lever in either of its two operative positions.

15. In a sh-tail propeller, a support, means to mount said support overthe end of a boat, a beam pivotally mounted in said support on avertical axis, one end of said beam extending into the boat and theother end extending to the rear of the boat and carrying a verticalsleeve, a propeller blade having a shaft pivotally journalled in saidsleeve, a lever journalled on an axis coincident with that of saidpropellers shaft, resilient means connecting said lever with saidpropeller blades shaft and continuously tending to maintain thepropeller blade in line with said beam, said beam being comprised ofsections detachably coupled together for purposes described.

16. In a fish-tail propeller, a support, means to mount said supportover the end of a boat, a beam pivotally mounted in said support on avertical axis, one end of said beam extending into the boat and theother end extending to the rear of the boat and carrying a verticalsleeve, a propeller blade having a shaft pivotally journalled in saidsleeve, a lever journalled on an axis coincident with that of saidpropellers shaft, resilient means connecting said lever with saidpropeller blades shaft and continuously tending to maintain thepropeller blade in line with said beam, said support comprising a clamp,a vertical sleeve pivotally mounted on the clamp to turn about ahorizontal axis, an arm carried by said last named sleeve and anadjusting screw carried by said last named arm for adjusting theposition of said last named sleeve and thereby adjusting the position ofsaid propeller blade with respect to the surface of the water.

17. In a fish-tail propeller, a support, means to mount said supportover the end of a boat, a beam pivotally mounted in said support on avertical axis, one end of said beam extending into the boat and theother end extending to the rear of the boat and carrying a verticalsleeve, a propeller blade having a shaft pivotally journalled in saidsleeve, a lever journalled on an axis coincident with that of saidpropellers shaft, resilient means connecting said lever with saidpropeller blades shaft and continuously tending to maintain thepropeller blade in line with said beam, and means continuously tendingto maintain said beam in a straight line with the boat.

HARRY CLAYTON MARTIN.

